/Engine/Source/Editor/UnrealEd/Public/Kismet2/BlueprintEditorUtils.h
Helper function to get all loaded Blueprints that are children (or using as an interface) the passed Blueprint
static void GetLoadedChildBlueprints ( [UBlueprint](API\Runtime\Engine\Engine\UBlueprint) * InBlueprint, [TArray](API\Runtime\Core\Containers\TArray)< [UBlueprint](API\Runtime\Engine\Engine\UBlueprint) * > & OutBlueprints )